New York — The UN expressed deep concern on Monday over the risk of escalation in Syria after US forces shot down a Syrian fighter jet and Iran fired missiles at a suspected Islamic State (IS) base in the east.
UN spokesman Stephane Dujarric said the UN was unable to independently confirm the downing of the Syrian jet on Sunday near the IS stronghold of Raqqa in eastern Syria or the Iranian claim that six missiles hit an "IS command base" in Deir Ezzor province.
The incidents "bring up more broadly our deep concern about the risk of possible miscalculation and escalation in the conflict in Syria", said Dujarric.
"We believe that this risk is heightened when efforts to combat Daesh and other listed terrorist groups are not combined with the pursuit of a comprehensive political solution to the Syrian conflict," he added. Daesh is the Arabic acronym for the Islamic State group.
Iran’s Revolutionary Guard said it launched a series of missiles into Syria on Sunday in revenge for deadly attacks in Tehran on June 7 that were claimed by IS.
Both Russia and Kazakhstan said on Monday the next round of Syria peace talks in Kazakhstan’s capital Astana has been scheduled for July 4-5.
Earlier, Russia warned it would track US-led coalition aircraft in central Syria as "targets" and halted an incident-prevention hotline with Washington.
Moscow has only once before suspended the hotline, which was established in October 2015 to prevent conflict between the different forces operating in Syrian airspace.
The incident and Russia’s response further complicate Syria’s six-year war and come as the US-led coalition and allied fighters battle to oust IS from Raqqa.
Analysts say neither Washington nor President Bashar al-Assad’s regime appear to be seeking further confrontation, but warn the risks are high in Syria’s increasingly crowded battlefields.
Russia’s foreign ministry accused Washington of failing to use the hotline before downing the jet, and called for a "careful investigation by the US command" into the incident.
"Any flying objects, including planes and drones of the international coalition, discovered west of the Euphrates river will be tracked as aerial targets by Russia’s air defences on and above ground", it warned.
The American Super Hornet shot down the Syrian SU-22 at about 7.00pm as it "dropped bombs near Syrian defence force fighters", the coalition said in a statement.
It said several hours earlier, regime forces had attacked the SDF in another town near Tabqa, wounding several and driving the SDF from the town.
The coalition said the Syrian warplane had been shot down "in accordance with rules of engagement and in collective self-defence of Coalition partnered forces".
Syria’s army disputed the account, saying its plane was hit while "conducting a mission against the terrorist ISgroup". It warned of "the grave consequences of this flagrant aggression".
Russia’s deputy foreign minister Sergei Ryabkov called it a "continuation of America’s line to disregard the norms of international law," adding: "What is this if not an act of aggression?"
Government forces meanwhile seized the town of Rusafa, south of Raqqa, a key stop on its path to Deir Ezzor and located near provincial oil and gas fields, the monitor said.
Syria’s war began in March 2011 with anti-government protests, but has since spiralled into a complex and bloody conflict that has killed more than 320,000 people and created millions of refugees throughout the region and in Europe.